Linear structure capturing and cutting apparatus

ABSTRACT

Apparatus for capturing and cutting a linear structure such as a cable comprising collector arms hingedly interconnected adjacent ends thereof, means for swinging distal ends of the arms away from each other to form an inverted V and for limiting the spread of the arms, shaped explosive charge means adjacent the interconnected ends for producing an explosive jet that is aimed or directed generally toward a captured linear structure, and means for initiating the shaped explosive charge means upon suitably capturing the structure or cable.

United States Patent Cole et al.

[54] LINEAR STRUCTURE CAPTURING AND CUTTING APPARATUS [72] Inventors: James K. Cole; Carroll A. Coonce; Harold N. Post, all of Albuquerque, N. Mex.

[73] Assignee: The United States of America as represented by the United States Atomic Energy Commission 22 Filed: Aug. 14,1910

21 App1.No.: 63,788

[52] U.S.Cl. ..l02/4, 102/9, 102/24 HC, 102/62 [51] Int. Cl. ..F42b 25/02, F42b 25/ 1 6 [58] Field ofSearch ..102/62, 35.2, 2411C, 88,4, 102/7.2, 9; 89/1 B [56] References Cited UNITED STATES PATENTS 2,920,532 1/ 1960 McBride 102/24 HC 1 June 20, 1972 1,304,549 5/1919 Du Pont ..89/1B 3,093,072 6/1963 Pigman l02/7.2 1,277,023 8/ l 9 l 8 Alexander ..102/62 3,382,800 5/1968 Biggs, Jr. .102/24 HC X 3,557,697 l/l971 Joyner et al. ..l02/4 Primary Examiner-Samuel W. Engle Attorney-Roland A. Anderson [5 7] ABSTRACT Apparatus for capturing and cutting a linear structure such as a cable comprising collector arms hingedly interconnected adjacent ends thereof, means for swinging distal ends of the arms away from each other to form an inverted V and for limiting the spread of the arms, shaped explosive charge means adjacent the interconnected ends for producing an explosive jet that is aimed or directed generally toward a captured linear structure, and means for initiating the shaped explosive charge means upon suitably capturing the structure or cable.

8 Claims, 7 Drawing Figures SHEET 10F 2 INVENTORS JAMES K. COLE CARROLL A. OOONOE HAROLD N. POST LINEAR STRUCTURE CAPTURING AND CU'I'IING APPARATUS BACKGROUND OF INVENTION There are instances where it may be desirable to destroy or cut elongated or linear structures to achieve some desired result. These linear structures may be cables, wires, truss members, antennas, communication lines, or any other struc tural member having a substantially longer dimension compared to its cross section in various forms such as a suspension bridge or the like. Such structures can inherently withstand tremendous overpressures without being severed or damaged, particularly cables or wires, and can generally not be destroyed without almost direct emplacement of a high explosive or other high pressure producing device against the structure. It may be difficult in many situations, such as in remote or hostile locations or environments, to emplace an explosive with sufficient accuracy to insure destruction or cutting of the structure. The more remote or hostile the environment or location, the more difficult the job of emplacing the explosive.

The accuracy of explosive emplacement may be partially offset by increasing the amount of explosive used, and thereby the overpressure produced, however, the amount of explosive needed increases rapidly with increasing distance of explosive placement. Further, the weight of explosive required to insure structure destruction or severe damage may become prohibitive with respect to the ability to deliver the explosive to the target and to the economy of target destruction.

In many of these applications, the location of the linear structure may be such that the only access thereto is by air delivery of an explosive munition. Not only must these applications require an air deliverable capability, but the location may be such that the munition must be delivered from high speed aircraft with the attendant lower accuracy capabilities, which become particularly critical in cutting or destroying such targets as a single or multiple cables.

Such target destructions are thus faced with the problem of positioning an. explosive sufficiently close to the target to effect destruction or damage thereof and then initiating the explosive at the best possible position thereof without undue size, complexity or weight of the system.

SUMMARY OF INVENTION In view of the above, it is an object of this invention to provide a novel apparatus and system for capturing and cutting a linear structure like a cable.

It is a still further object of this invention to provide cable capturing and cutting apparatus which is of simple construction and small size and low weight.

It is a still further object of this invention to provide a cable cutting apparatus which utilizes a relatively small explosive warhead. It is a still further object of this invention to provide a cable cutting apparatus which is capable of intercepting and capturing the cable target and then accurately positioning an explosive warhead adjacent to the cable target for destruction thereof.

Various other objects and advantages will appear from the following description of the invention, and the most novel features will be particularly pointed out hereinafter in connection with the appended claims. It will be understood that various changes in the details, materials and arrangements of the parts, which are herein described and illustrated in order to explain the nature of the invention, may be made by those skilled in the art.

The invention comprises a linear structure capturing and cutting apparatus having collector arms, means for rotatively supporting the arms adjacent one end thereof, means for urging the arms away from each other to form an inverted V, a shaped explosive charge means for producing an explosive jet directed generally toward the apex of the arms or a captured structure that is to be cut, and means for initiating the shaped explosive charge means upon capturing the structure between the arms.

DESCRIPTION OF DRAWING The present invention is illustrated in the accompanying drawings wherein:

FIG. 1 is a side elevation view, partially fragmented and cross sectioned, of a linear structure capturing and cutting apparatus incorporating features of this invention;

FIG. 2 is a side elevation view of the apparatus of FIG. 1 in its folded in-flight configuration;

FIG. 3 is a side elevation view of the apparatus of FIG. I in the opened in-flight configuration;

FIG. 4 is a perspective, somewhat simplified view of a shaped explosive charge and fuze mechanism which may be used with the apparatus of FIG. 1;

FIG. 5 is a perspective view of an air deliverable cable cutting system using a plurality of the apparatus illustrated in FIGS. 1 or 5;

FIG. 6 is a perspective of another embodiment of this invention; and

FIG. 7 is a perspective view of a shaped explosive charge which may be used in the embodiment of FIG. 6. DETAILED DESCRIPTION In order to provide an effective linear structure (such as a cable or wire) destruction apparatus or system, it is desirable that the apparatus or system have a high probability of intercepting the target, or acquiring or capturing the target, of positioning the target in a location adjacent to the munition warhead, and then of producing sufficient overpressure or other destructive mechanisms to destroy or significantly damage the target. These capabilities are exhibited by the apparatus shown in FIG. 1. In this apparatus, collector arms or legs 10 and 12 are hinged or otherwise rotatably supported about a pin or shaft 14 at one end of the arms to permit rotative movement thereabout. A suitable spring 16 may be fastened to one or the other or both of the arms 10 and 12 near pin 14 so as to urge the arms away from each other at their distal ends about pin 14 to form an inverted V theretogether. Ann 10 is preferably made of a channel having dimensions sufficiently large to receive, at least partially, arm 12 within the walls of the channel when the apparatus is in the folded condition. The spread and the angle between arms 10 and 12 may be limited to some desired position by a pin 18 mounted transversely through arm 12 and the shape and position of the heel 20 of arm 10. At the desired spread of the arms, heel 20 will come in contact with pin 18 and be urged thereagainst by spring 16.

Arm 12 may also be made of a channel which is adapted to receive and carry various parts of the apparatus and may be faced in the same open ended direction as the channel of arm 10, as shown. The munition includes a suitable fuzing mechanism 22 and a shaped explosive charge 24 appropriately mounted within the channel of arm 12 with the shaped explosive charge positioned so as to direct the explosive jet produced thereby toward a captured cable or the apex of the hinged arms 10 and 12, as will be described in greater detail with respect to FIG. 4. The explosive jet may be produced when a cable or other linear structure actuates a trigger cable 26 or other triggering mechanism associated with the fuze mechanism 22. Trigger cable 26 may be fastened to arm 10 by any appropriate means so as to permit its removal or similar activation by the linear structure as it passes or engages the triggering cable. An air stream, which operates on the fuze mechanism 22 to arm the munition, may be provided by a baffle or air scoop 28 fast ened across the interior of the channel of arm 12 aligned with an opening 30 passing through the wall of arm 12.

Arms 10 and 12 may be made of any appropriate lightweight material such as aluminum, high impact plastic or honeycomb materials and be provided with various openings, such as openings 32 and 34 in the walls of the arms, to decrease the weight thereof. These openings may also function to provide some aerodynamic stability to the apparatus by producing a desired air flow through the arm channels. Additional stability may be achieved by tapering the channels of arms and 12, as shown, in width and depth and by positioning weighted members 36 and 38 at the distal ends thereof. If it is desired, rails or slides 40 and 42 may be positioned along the channels at the inner surfaces thereof which are made of materials, such as hardened steel or certain plastics, having a lower coefiicient of friction than the materials of which the channels are made to increase the capture probability of the collector arms 10 and 12, especially when the linear structure target is engaged or intercepted at or near the distal ends of the arms 10 and 12, as will be described in greater detail below.

In their stored and initial flight configuration, arms 10 and 12 are folded together with arm 12 partially within the confines of the channel walls of arm 10, as shown in FIG. 2. As the apparatus is initially dropped or otherwise propelled toward the linear structure target in the folded configuration the arms may be stabilized by any appropriate means such as by streamer 44 attached to the hinged end of the arms. Streamer 44 may be any appropriate stabilizing streamer, such as one having a plurality of air pockets 46 disposed along the streamer with open ends facing in the direction of flight. Streamer 44 may be appropriately packed within area 48 of arm 12 or any other convenient location.

Arms 10 and 12 may be held in the folded position by any appropriate fastening means, such as a time delayed line cutter 50 which after some predetermined period will release he arms and permit spring 16 to spread them into their unfolded configuration shown in FIG. 1 and in FIG. 3. When the arms are unfolding or unfolded, streamer 44 may be separated from the apparatus and a parachute 52 released with the shrouds coupled or attached to the apex of the arms to provide additional stability and some desired terminal velocity. Parachute 52 may also be stored within space 48 of arm 12 until it is needed. Streamer 44 and parachute 52 may be released at the appropriate times by any conventional time delay and releasing means in a well known manner, such as by line cutter 50 and/or the air stream about the apparatus. Streamer 44 may be eliminated, if desired, however it provides stability during the initial flight of the apparatus at which time, particularly if a plurality of these apparatus are utilized in a simultaneous release system, a parachute could present a tangling problem with other parachutes.

As the apparatus continues its flight in the open configuration of FIG. 3, the air flow through the opening 30 and along baffle 28 may arm fuze mechanism 22 after an appropriate delay. When the apparatus reaches the target, the target may be intercepted by one or the other of the arms 10 or 12, and possibly hit directly at the apex thereof, such as shown by the dotted circles 60a, 60b and 600 representing a cable target. If the target strikes an arm within the effective capture length of the apparatus, the target will slide along the arm which it engages towards the apex of the arms until it reaches trigger cable 26, initiating the fuzing mechanism 22 and the shaped explosive charge 24. With the proper delay time built into fuze mechanism 22, the shaped explosive charge 24 will ignite when the target reaches or is near the apex of the arms and sever or otherwise damage the target. If it is desired, a spring leaf type catch arrangement may be positioned along the sidewalls of one or both of the arms 10 and 12 which will deflect as the target passes over the spring and then return to its initial position across or partially across the apex of the arms and act to further insure capture of the target by the arms and holding of the target at a location which will insure maximum damage thereto.

The maximum efiective capture width or length of the arms is dependent upon the position of the center of gravity of the apparatus, its configuration, and the coefficient of friction of the arms. This latter function, that is the coefficient of friction of the arms, becomes more critical at or near the distal ends of the arms. Thus, the positioning of slides 40 and 42 may increase the maximum effective capture length of a given apparatus. If the target strikes an arm within the maximum effective capture length, such as at a position designated by 60a,

the target may proceed along the arm to the apex. However, if the target is outside the maximum effective length, the apparatus will be unstable and will rotate about the target and fall off to the side without capture or positioning thereof.

It has been found that the effective capture length may be maximized and be about percent of the arm spread by positioning arms 10 and 12 at an angle of about 60 to that is at an angle of about 30 to 45 between the direction of flight and one of the arms. Smaller angles increase the probability of capture upon a target intercept while larger angles increase the probability of an intercept while increasing the possibility of having the target hit an arm of the apparatus outside of the effective capture length.

The fuze mechanism 22 and shaped explosive charge 24 are shown in greater detail in FIG. 4. The shaped explosive charge 24 includes a linear-shaped explosive 62 configured on one side with a V-shaped indentation 64. Explosive 62 is enclosed within an appropriate housing 66 which is made of a material, particularly along the walls of the indentation 64, which may produce a jet of molten metal when the explosive is initiated due to the lens effect produced by indentation 64.

Fuze mechanism 22, which is shown with a face plate removed to illustrate a portion of the apparatus which makes up the fuze mechanism, includes a fan or rotor 68 which is coupled to the air stream flowing through opening 30 and baffle 28 of arm 12. The fan 68 rotates a rotor 70, which carries a detonator 72, through an appropriate gearhead 74 and pulley arrangement. As rotor 70 is rotated, detonator 72 is moved into position in alignment with and adjacent to a firing pin carried by the detonator spring 76. Detonator spring 76 is held in a preloaded, flexed condition by trigger cable 26 so that when the trigger cable 26 is pulled by a target approaching and reaching the apex of arms 10 and 12, the detonator spring may be released and the firing pin impacted against detonator 72 to initiate an explosive train which will in turn ignite explosive 62. It can be seen that the explosive cannot be fired unless the apparatus travels through the air a sufficient distance and at a sufficient speed to permit rotor 70 to turn a sufficient amount to place detonator 72 in alignment with the firing pin on spring 76.

Fuze mechanism 22 may also be provided with a clean-up fuzing mechanism which will initiate the explosive if the apparatus does not intercept and capture a target before impacting on the ground or another surface. Such a clean-up may be achieved by placing an acceleration sensing device, such as an overloaded column which is held in an initial position by rotor 70 but which is freed to move by the rotation of the rotor to the armed condition. The overloaded column may be used to hold a spring driven piston from movement until the column senses a force (impact against the ground) which bends the column away from the piston releasing the piston. The piston may then be used to remove trigger cable 26 from its safing position between the trigger spring and the detonator. A time delay may be built into this actuation so as to insure that if the actuation is initiated by the impact of a target against an arm of the apparatus that the explosive will not be initiated before the target can slide to a position near the apex of the arms.

The apparatus may be made with more than two arms which are rotatably or swingably coupled adjacent one end with an appropriately shaped explosive charge which will produce an explosive force and explosive jet towards all the intercept possibilities of respective arms. The arms can be channel shaped, as described above, or possibly with telescoping rods. However, it has been found that by using a plurality of the devices as shown in FIGS. 1, 2 and 3, that a probability of intercept, acquisition, positioning and severing of a target may be as high with a two arm apparatus as it is with an apparatus having more than two arms, particularly when it is found that a greater number of the two arm apparatus can be packaged together to get maximum area coverage. The weight and size of the individual two arm apparatus may be minimized since the additional legs or arms will require additional weight and space as well as a larger, heavier and more complicated shaped explosive charge.

A linear structure cutting system may comprise a plurality or cluster of these apparatus packaged in a single, deployable cannister, such as by a cannister 80 shown in FIG. 5. The individual apparatus may be bundled together as shown by 82 within cannister 80 and deployed by aircraft or fired by a rocket or shell arrangement. Cannister 80 may be made of two halves 84 and 86 which may be separated upon cannister 80 reaching a desired position with respect to the target. The capturing and cutting apparatus may then be released from their bundled condition and dispersed by the air stream towards the target. As the apparatus are dispersed, they will assume the various configurations shown in FIGS. 2 and 3 until target acquisition or clean-up destruction.

In one application, arms and 12 may taper in size from about 1.75 by 2.25 inches at the hinged end to about 1.25 by 0.75 inches at the distal end with an overall length of about 34.5 inches. With an angle of about 60 between the unfolded arms, the spread of the distal ends will be about 34.5 inches with a maximum effective capture width of about 30 inches. When folded, the apparatus uses about 2.5 by 2.5 by 34.5 inches of space. Each apparatus weighs about 7 pounds with about 1 pound weights at the distal ends and about 5 ounces of explosive. Suitable aerodynamic stability and terminal velocity may be achieved with a streamer about 70 inches long and a parachute about 12 inches in diameter.

FIG. 6 illustrates a four legged linear structure capturing and cutting apparatus which utilizes a central member 86 which may be utilized where increased size, weight and complexity may not be as critical. Member 86 may be weighted at its lower end to provide the desired stability and be provided at its upper end with a parachute storage, fuzing, and explosive charge section 90. The arms or legs may be urged outward by suitable springs, such as springs 92, which may also act to capture the target as the target deflects the spring away from the respective arms. With such an arrangement, the explosive charge should be configured as shown in FIG. 7 with a plurality of explosive lenses radially distributed about the explosive so as to produce an explosive jet towards the apex of each arm with member 86 and at the apex of each pair of adjoining arms.

Such an apparatus is capable of severing a steel cable l.5 inches or more in diameter positioned near the apex of the arms in front of the explosive jet. Using an air delivery system as shown in FIG. 5, a high probability of target intercept, capture, positioning and severing may be achieved.

What is claimed is:

1. An apparatus for capturing and cutting a linear structure comprising first and second collector arms, hinge means rotatably interconnecting said arms adjacent one end thereof, means for urging distal ends of said arms away from each other about said hinge means to form an inverted V, means for limiting the spread of said arms, means including a parachute having shrouds attached adjacent the apex of said arms for stabilizing said apparatus during movement and for guiding said arms toward said structure with the distal ends of said arms facing said structure, shaped explosive charge means adjacent said hinge means for producing an explosive jet directed generally toward a said captured linear structure, and means for initiating said shaped explosive charge means upon capturing said structure between said arms near the apex thereof.

2. The apparatus of claim 1 wherein said arms are channel members tapering toward said distal ends.

3. The apparatus of claim 2 wherein the channel of said first arm is larger than the channel of said second arm so as to at least partially house said second arm when said arms are in closed relationship.

4. The apparatus of claim 3 wherein distal ends of said arms are weighted and carry a slide member.

5. The apparatus of claim 4 wherein said initiating means is mounted in said second arm.

6. The apparatus of claim 5 wherein said initiating means includes means for arming thereof after predetermined air travel and means for detonating said initiating means thereafter upon impact.

7. The apparatus of claim 1 including a plurality of said arms hinged adjacent a common end and cooperating to form a plurality of pairs of arms.

8. The apparatus of claim 1 wherein said arms are at an angle from about 60 to to each other when unfolded. 

1. An apparatus for capturing and cutting a linear structure comprising first and second collector arms, hinge means rotatably interconnecting said arms adjacent one end thereof, means for urging distal ends of said arms away from each other about said hinge means to form an inverted V, means for limiting the spread of said arms, means including a parachute having shrouds attached adjacent the apex of said arms for stabilizing said apparatus during movement and for guiding said arms toward said structure with the distal ends of said arms facing said structure, shaped explosive charge means adjacent said hinge means for producing an explosive jet directed generally toward a said captured linear structure, and means for initiating said shaped explosive charge means upon capturing said structure between said arms near the apex thereof.
 2. The apparatus of claim 1 wherein said arms are channel members tapering toward said distal ends.
 3. The apparatus of claim 2 wherein the channel of said first arm is larger than the channel of said second arm so as to at least partially house said second arm when said arms are in closed relationship.
 4. The apparatus of claim 3 wherein distal ends of said arms are weighted and carry a slide member.
 5. The apparatus of claim 4 wherein said initiating means is mounted in said second arm.
 6. The apparatus of claim 5 wherein said initiating means includes means for arming thereof after predetermined air travel and means for detonating said initiating means thereafter upon impact.
 7. The apparatus of claim 1 including a plurality of said arms hinged adjacent a common end and cooperating to form a plurality of pairs of arms.
 8. The apparatus of claim 1 wherein said arms are at an angle from about 60* to 90* to each other when unfolded. 